Device for preventing back-firing, capable of being used as theft-preventing devicesfor any applications



April 9, 1935.

G. DORES r:r AL 1,996,861 DEVICE FOR PREVENTING BACKFIRING, CAPABLE OF BEING USED AS THEFT PREVENTING DEVICES FOR ANY APPLICATIONS Filed ONE-24, 1930 I 1 w $1 mm r 50 in th chamber 2 and flow, through the port 4, -1. In an apparatus for security against back- Patented Apr. 9, 1935 V V 7? V r I UNITED STATES PATENT OFFICE DEVICE FOR REVENTING BACK-FIRING, .OAPABLE OF BEING USED AS THEFT-PIKE! VENTINGV DEVICES FOR ANY APPLICA-I TIONS h a V Gaston bore'sgParis, and Lucien Girard, Montrouge, France T Application October 24, 1930, Serial No. 490,994

In France October '28, 1929 7 6 Claims. (01. 123-142) This invention relates to improvements in nited gases enter theport 4 and the open end 6 Safety apparatus for avoiding the return of'igof the tubularmember 5, they flow through this nited gases to the carburettor feeding an engine. tubular member towards the valve 8, which The improved safety apparatus according'to theylift in order to beevacuated outside the 5 the invention isg arranged between the inlet pipe apparatus. -J for the ,carburetted mixture of the engine and In the other Figures 2, 3 and 4 of the drawings, the ca bur ttor;

- a a the same .or similar parts are designated by the This apparatus comprises in combination: "a same reference numbers, and the general operacasing forming a chamber and having an inlet tion previously indicated is the same. In the 0: communicating with the carburettor and an outfforms of constructionillustrated. in Figs. 2, 3 10 let communicating with the engine, a tubular and 4, the safety'a'pparatus is completed by obtuj member having an end which opens in an opporating members allowing," upon return of the igsite direction to the inlet and projects into the nited gases, to cut ofi the communication between V chamberin the casing to a point near the outthe engine and the carburettor. let, the other end of the tubular member opening In the example shown in Fig. 2, asmall piston 15, to the atmosphere, the outer surface of the tubul 0, movable intranslation in the tubularmember lar member being spaced from the internal wall-of 5, is rigid'with the valve l I of which it 'formsthe thes aid chamber to provide an annular passage rod.. a v g for the sucked mixture. During normal feeding of the engine, the valve Th'e invention has for further object various ll occupies'the position'shown in Fig. 2. In 20 forms of construction which will appear from the case of return of the ignited gases, the latter following description with reference to the acact on the small piston lllandevenon'the valve companying drawings, given by way'of example II which then closes the port 3, the ignited gases only, in which: flowing, through the tubular member 5, to the Figs. 1, 2, 3 and 4 respectively illustratain eleatmosphere, by lifting the valve 8. f vation and axial longitudinal section, four forms In the example shown in Fig. 3, the small pisof construction of an apparatus according to the ton. I0 is connected, by links 12, to two flapping invention. members l4 pivoted about a shaft [5. In case Fig. 5 is an explanatory figure showing the of return of ignited gases, the piston ID, on which V position of the apparatus, illustrated in Fig. 2, these gases act, actuates, through the medium of between a carburettor-and an engine fed by this the links l2, the flapping members l4 which obcarburettor. H r V turate'the port 3. r

In the first form of construction illustrated in "In the example shown in Fig. 4, the casing l i 1, the app ra ompri a casing l formcomprises an extension constituted by a guide 0 mg a ham r 2 a d av an i et 3 or the member for a tubular. obturator l6 constantly combustible mixture entering the carburettor, ur ed upwardlyby a weak spring H, In case of and anoutlet 4 for directing the combustible return of ignitedgases, the tubular obturator I 6 m tu e wal ds the n e- Defiecting a s is moved downwardly and exactly fitsagainst the form of a tubular m m av p the open end 6 of. the tubular member 5, thus 40' end 5 arranged Opp i the Outlet 4 d directed cutting ofi the communication between the inin reverse direction to the inlet 2, opens to the let 3 a d the outlet Aand'cQnStituting; with the atmosphere through its other end 1 Controlled by tubular-member 5, a single channel directing the a Valve urged 130 closed Position y a Sp 9- ignited gases towards the exterior, these gases v The tubular member 5 isso arranged that its outer lifti th val e 8, g v walls and theinner walls of the chamber 2, limit Fi 5 shows, by way ofzindication, theposition a substantially annularspace inwhich circulate, f the apparatus, illustrated in 2, between du g the feeding r Of the n in a carburettor 20 and-anengine 2i. 7 r the combustible gases coming from the carbu- What we claim as our invention and desire to rettor, these gases, which enter the inlet 3,-.pass secure by Letters Patent is:

towards the engine. During this normal feeding firing for preventing the ignited gases on the reperio'd, the valve '8 closes the end 1 of the tubular turnpath from reaching a carburettor for feedmember 5, in order to avoidany admission of air. ing an engine, the arrangement of an apparatus In case ignited gases coming, from the engine between the inlet pipe for thecarburetted mixture should return towards the carburettor, these isof theengine and said carburettor, said apparal i an annular passage for the sucked mixture, ob;

tus comprising in combination a casing forming a chamber and having an inlet communicating with the carburettor and an outlet communicating with the engine, a tubular member having an end which opens in an opposite direction to the inlet and projects into the chamber in the casing to a point near the outlet, the other end of the tubular member opening to the atmosphere, the outer surface of the tubular member being spaced from the internal wall of the saidchamher-to provide turating means associatedwith the outlet end of the tubular member for preventing the admission of air into the said tubular member, but allowing the evacuation from said tubular-member] to the exterior, so that during the normal running period, the sucked mixture passes through? the annular space from the carburettor. towards the engine and, in the case of thereturn of ignited gases from the engine towards'the carbu rettor, the-inlet of said tubular memberrentrains and directs said gases to the obturating means and thence to the atmosphere;

2. In -an apparatus for security against backfiring for preventing'the ignited gases on the return path fromreaching a carburettor for feeding an engine, the arrangement'of an apparatus between the inlet pipe for the carburetted mixture of the engine and said carburettor, said apparatus comprising in combination a casing forming a chamber and havingan inlet communicat-' ing with the carburettor and an outlet communi-. eating with the engine, a tubular member having an end which opens in an opposite direction to the inlet and projects into the chamber in the casing to a point'near the outlet, the other end of the tubularmember opening to the atmosphere, the

- outer surface of the tubular member being spaced from the internal wall of the said chamber to provide an annular passage for the sucked mixture, a valve for controlling the .end of the tubular member opening'in the atmosphere, for preventing the admission of air into the said tubular member but allowing the evacuation from saidtubular member to the exterior, means for automati cally restoring said valve toits closing position, a second valve allowing only the passage of the mixture from the carburettor to the engine, a small piston being movable, in translation in the tubular member, means for connecting said small piston to said second valve in such a manner that the piston forms the stem of the valve so that the return of the ignited gases acting-on-the small piston facilitates the displacement of the second valve for cutting off the communication between said casing and said carburettor and so that; during the normal running period, the sucked mixture passes through the annular space from the carburettor towards the engine and, in the 7 case of the return of ignited gases from the engine towards the carburettor, the inlet of said tubular member entrains and directs said gases to the first valve and thence to the atmosphere.

3. In an apparatus for security against backfiring for preventing the ignited gaseson the re turn path from reaching af carburettor for feeding an engine, the arrangement" of an apparatus between the inletpipe'for the carburetted mixture of the engine and said carburettor, said apparatus comprising combination a casing forming a chamber and having an inlet communicating with the carburettor and an'outlet.

communicating with the'engine, a tubular member having an end which opens in'an opposite terior, mansfor automatically restoring said valve to its closing position, two flapping members pivoted aboutone and the same fixed shaft and allowing only the passage of the mixture from the carburettor to the engine, a small piston movable'in translation in the tubular member,

links for connecting the small piston to said flapping members so that the returnof the -ignite'd gases acting on the small piston facilitates the displacement of the flapping members for cutting off the communication; between said casing and said carburettor, and so that, durin the normal running period, the sucked mixture passes through the annulauspace from the carburettor towards the engine and, in the case of the return of ignited gases fromthe engine towards the carburettor, the inlet of said tubular member entrainsand directs said gases to the Valve and thence tothe atmosphere. g

4. In an apparatus for security against backfiring for preventing the ignited gases on the return path from reaching a carburettor for feeding an engine, the arrangement of an apparatus between the inlet pipe for the carburetted mixture of the engine and said carburettor, said apparatus comprising in combination a casing forming a chamber and having an inlet communicating with the carburettor and an outlet communicating with the engine, a tubular member having an end which opens in an opposite direction to the inlet, and projects into the chamber in the casing to .a point nearthe outlet, the other end of the tubular member opening to the atmospherathe outer surface of the tubular member being spaced from the internal wall of the saidchamber to provide an annular passage for the sucked mixture, a valve for controlling the; end of the tubular member opening in the atmosphere, for preventing the admission of air into the said tubular member but allowing the cluding in combination with the suction pipe o f an internal combustion engine, a casing having an inlet and outlet interposed in the suction pipe and also provided with a relief port communieating with the atmosphere, valve means for the port acting to normally prevent admissionof outside air and deflecting means means within the casing and extending from the port to a point near and opposite the outlet and acting to allow the normal passage of liquid fuel from the inlet to the outlet but entraining a back firing charge from the outlet and directing it to the relief port so that it will be exhausted by the valve means. 7 a

6. Apparatus of the character described ineluding in combination with the suction pipe of an internal combustion engine, a casing having an inlet and outlet interposed in the suction pipe and also provided with a relief port communieating with the atmosphere, valve means for the port acting to normally prevent admission of outside air and deflecting means within the casing and extending from the port to a point near and opposite-the outlet and actingto allow the normal passage of liquid fuel from the inlet to the outlet but entraining a back firing charge from V the outlet and directing it to the relief port, and additional valve means mounted in the casing for allowing the normal passage of liquid fuel thereto but closing under thevaction of a back firing charge to prevent the passage of the latter rearwardly through the inlet.

GASTON DORESL LUCIEN GIRARD; 

